Temperature controlled actuating mechanism



p m an A. WEST 2,439,706

TEMPERATURE CONTROLLED ACTUATING MECHANISM Filed Feb. 23, 1946 IN VEN TOR.

Patented Apr. 1a, 1948 UNITED STATES PATENT OFFICE TEMPERATURE comounn ACTUATING MECHANISM.

Charles A. West, Southbrldge, Mass. Application February 23, 1943, lilo. 349,343

This invention relates to mechanism adapted to perform a mechanical operation, such as opening or closing a valve, under the automatic control of a temperature-responsive device.

It is the general object of my invention to improve the construction of such mechanism as heretofore known, in such manner as to eflfect substantial reduction in size, weight and cost,

' proved actuating mechanism; I

Fig. 2 is a sectional plan view of certain parts, taken along the general line 2-2 in Fig. 1; and

Figs. 3, 4 and 5, are sectional views showing modified detail constructions to be described.

Referring to the drawings, my improved actuating mechanism comprises a casing l having a depending open frame portion H adapted to be mounted on a valve l2 of any suitable construction, provided only that the valve may be opened and closed by axial movementof a valverod ll slidable in a gland IS.

The valve rod I4 is mounted in a rotatable threaded sleeve or tubular nut l3 and may be secured in axially adjusted position by a lock nut I1. The sleeve I3 is slidable in a collar i3, and a shoulder on the sleeve I3 is normally held against the collar l3 by a coil spring 23 which at its upper end engages a thrust member 2|.

The sleeve l6 and spring 23 provide a safety release for the valve l2 if the temperature continues to rise and the pressure continues to increase after the valve i2 is fully closed. In this event, the collar I3 is pushed downward along the sleeve l3 and no damage is done to the valveactuating mechanism.

The thrust member 2i has an upward projection 22 having a rounded end seated in a semispherical depression in a cap 23. The cap 23 is connected by a tubular bellows member 23 to the 3 upper face of the casing Ill. The edges of the bellows member 23 may be firmly secured in the cap 23 and to the casing Hi by soldering the edges in grooves or recesses in said parts or in any other suitable manner.

A cover 21 surrounds the bellows member 25 and cap 23 in spaced relation and is similarly permanently secured to the upper portion of the 3 Claims casing l3. An annular pressure chamber 0 is thus provided between the inner face of the cover 21 and the outer face of the bellows member 23. together with the top surface of the cap 23.

3 The cap 23 is of slightly larger diameter than the bellows member 23 to avoid wear on the latter. The cover 21 in effect constitutes the upper part of the casing 13 and is to be considered a part of the casing in the interpretations of the 10 claims.

' The valve rod I 3 is normally held upward to open the valve l2 by a pair of heavy tandem coil springs 33 and 3|. The upper spring 33 is centered at its upper end by a shouldered downward l3 projection of the thrust member 2| and at its lower end is seated on a flanged collar 32. The upper end of the lower spring 3| is similarly seated in'a flanged collar 33, and the lower end thereof is seated in a flanged collar 34 having so radial openings 33 by which it may be turned.

The flanged collars 32 and 33 oppositely-engage a ring 31 which is loosely slidable on a tube 33. The ring 31 may be of bronze, plastic or any other suitable and preferably self-lubricating 23 material.

The tube 33 is secured at its upper end to a further downward projection 43 of the member 21 and at its lower end is secured to the collar l8 previously described. The flanged collar 34 has a sleeve-like upward outer extension 43 which is threaded to an internal portion 43 of the casing M.

A member 33 is secured in the downwardly extending open frame portion ll of the casing l3, and antifriction rolls 3| (Fig. 2) are pivotally mounted in the member 33, with slight clearance of the tube 33. The tube 33 is thus vertically centered and guided by said rolls.

A fluid-filled device D which is responsive to temperature changes is connected by a tube 33 and coupling 33 to a passage 31 which communicates with the chamber C between the cover 21 and the bellows member 23.

A filler extension 33 of the casing I 3 may be provided, which extension is normally enclosed by a cap 33 after the filler tube 33 has been. sealed.

The device D is to be placed wherever the temperature is to be controlled and is partially filled with ,a temperature-responsive liquid. The tube 33 extends nearly to the closed end of the device D, so that on rise in temperature and expansion or the fluid in the device, a portion of the liquid will be forced upward through the tube 33 to the chamber 0 and will thus depress the cap 23, the thrust member 2|, the tube a and the valve 3 stem M. This closes the valve V to the extent indicated by the rise in temperature.

Lateral displacement or buckling of the springs 30 and 3| on compression is substantially prevented by providing two relatively short springs instead of a single long spring, and by providing the sliding ring 31 and the flanged collars 32 and 33 all centered on the tube 38. The lower end of the tube 38 being closely guided by the rolls straight-line motion of the valve rod I 4 is assured and sidewise pressure on the gland I5 is substantially avoided.

The device is adapted ior different operating temperatures by selecting a liquid for the device D which has the desired temperature range. The pressure to which the mechanism responds may be adjusted by turning the flange member 34 and sleeve 43 in the casing portion 44, thus adjusting the flange member 34 upward or downward. During such adjustment, all parts associated with the sleeve 43 and flange member 34 rotate therewith, and the thrust member 2| turns easily in its bearing 22 in the cap 23.

In Fig. 3 I have shown a modified construction in which the cap 62 has a conical recess 63 to receive a ball 64 which is also seated in a semispherical recess 65 in the upper end of a thrust member 66, which corresponds to the thrust member 2| in Fig. 1.

In Fig. 4 I have shown a modified construction in which the flanged collars 32 and 33 and the ring 31 are replaced by a single-flange ring slidable on the tube 38 previously described.

In Fig. 5 I have shown a further modification of the guide ring between thesprings 30 and'3i in which antifriction rolls are mounted in spaced relation in a ring 76 provided with springcentering flanges 71 and 18.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

l. Mechanism for moving a valve under control of a fluid-filled device which is responsive to temperature, changes, said valve-moving mechanism Number comprising a frame, a casing, a bellows member fix d at its lower end to said casing and fixed at its upper end to a cap movable longitudinally oi said casing on compression or expansion of said bellows member, said casing. bellows member and cap defining an enclosed space exterior to said bellows member and in communication with said fluid-filled device, a thrust member engaging and depressible by said cap, a tube depending from said thrust member and operatively connected to the valve to be moved, a guiding support adjustably secured in said frame and in which the lower end of said tube is freely slidable, a spring-centering guide member freely slidable on the middle portion or said tube, a coil spring loosely encircling said tube and interposed between said thrust member and said guide member, and a second coil spring also loosely encircling said tube and interposed between said guide member and said tube-guiding support, and said two springs being centered and held clear of said tube by por-' tions of said thrust member, said guide member and said tube-guiding support which project within the end portions of said springs.

2. The combination in a valve-moving mechanism as set forth in claim 1, in which a swivel bearing is provided between the cap and the thrust bearing to facilitate alignment of the parts.

3. The combination in a valve-moving mechanism as set forth in claim 1, in which the two coil springs are of opposite hand whereby the tendency to transverse displacement is reduced.

CHARLES A. WEST.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date McElroy Mar. 22, 1892 Moyle Apr. 27, 1915 Mallory Oct. 11, 1927 Giesler Nov. 1, 1932 Carson Nov. 21, 1933 

